Jims86
Full Access Member
- Joined
- Aug 3, 2010
- Posts
- 5,492
- Reaction score
- 135
- Location
- Patterson,Ca
- First Name
- Jim
- Truck Year
- 1986
- Truck Model
- K10 Suburban Silverado
- Engine Size
- 5.7 TBI
Or may be thinking of installing true dual exhaust on a TBI truck.
This post is intended for anyone in my situation, where they have to pass emissions tests, and have swapped in a GM TBI system.
Since I have decided to stay with TBI, i have been chasing down a problem with the EGR system, throwing code 32.
Today I found the problem.
I am still running the dual cat exhaust, with magnaflow mufflers inline, and dual 2" tailpipes(like what came on the 86 trucks from the factory)
This exhaust configuration is entirely too free flowing for the TBI EGR system to work properly, as this particular EGR system is disigned to operate with the help of back pressure from the original single cat ehaust system, found on un-molested 87-95 GM light Trucks.
I have cured the problem by stuffing one of the tailpipes with tightly rolled shop rags....no code 32.
I have confirmed this by removing the rags, and then driving at 55 mph, and code 32 comes back up, when pressing on the accellerator to maintain speed.
I also noticed a tiny bit more of low end grunt with the tailpipe plugged up.
This post is intended for anyone in my situation, where they have to pass emissions tests, and have swapped in a GM TBI system.
Since I have decided to stay with TBI, i have been chasing down a problem with the EGR system, throwing code 32.
Today I found the problem.
I am still running the dual cat exhaust, with magnaflow mufflers inline, and dual 2" tailpipes(like what came on the 86 trucks from the factory)
This exhaust configuration is entirely too free flowing for the TBI EGR system to work properly, as this particular EGR system is disigned to operate with the help of back pressure from the original single cat ehaust system, found on un-molested 87-95 GM light Trucks.
I have cured the problem by stuffing one of the tailpipes with tightly rolled shop rags....no code 32.
I have confirmed this by removing the rags, and then driving at 55 mph, and code 32 comes back up, when pressing on the accellerator to maintain speed.
I also noticed a tiny bit more of low end grunt with the tailpipe plugged up.